[PATCH 11/20] Inline get_page_from_freelist() in the fast-path

[Mel Gorman]

In the best-case scenario, use an inlined version of
get_page_from_freelist(). This increases the size of the text but avoids
time spent pushing arguments onto the stack.

Signed-off-by: Mel Gorman <mel@xxxxxxxxx>
---
 mm/page_alloc.c |   19 +++++++++++++++----
 1 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d0d8c07..36d30f3 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1393,8 +1393,8 @@ static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
  * get_page_from_freelist goes through the zonelist trying to allocate
  * a page.
  */
-static struct page *
-get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order,
+static inline struct page *
+__get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order,
 		struct zonelist *zonelist, int high_zoneidx, int alloc_flags,
 		struct zone *preferred_zone, int migratetype)
 {
@@ -1470,6 +1470,17 @@ try_next_zone:
 	return page;
 }
 
+/* Non-inline version of __get_page_from_freelist() */
+static struct page * noinline
+get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order,
+		struct zonelist *zonelist, int high_zoneidx, int alloc_flags,
+		struct zone *preferred_zone, int migratetype)
+{
+	return __get_page_from_freelist(gfp_mask, nodemask, order,
+			zonelist, high_zoneidx, alloc_flags,
+			preferred_zone, migratetype);
+}
+
 int
 should_alloc_retry(gfp_t gfp_mask, unsigned int order,
 				unsigned long pages_reclaimed)
@@ -1780,8 +1791,8 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
 	if (!preferred_zone)
 		return NULL;
 
-	/* First allocation attempt */
-	page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
+	/* First allocation attempt. Fastpath uses inlined version */
+	page = __get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
 			zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET,
 			preferred_zone, migratetype);
 	if (unlikely(!page))
-- 
1.5.6.5

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